Multiple swaggerUi with a single express app

Question

I'm trying to find a solution to have multiple swaggerUi documentation with a single express app.

I'm using :

"typescript": "^2.5.2",
"swagger-tools": "^0.10.1",
"express": "^4.15.3",
"express-openapi": "^1.0.1",

My swagger doc file is partly generated with the project file architecture.

How can I do that ?

EDIT ---

For now I'm initializing swaggerUi like this :

const openapi = Openapi.initialize({
    paths: openApiPaths,
    expressApp,
    swaggerApiDoc,
  });
const openApiSpec: any = openapi.apiDoc;
app.use(swaggerUI(openApiSpec));

Where openApiPaths contain the paths:{} of swagger doc

Answer 1

A year late, but still valid:

async function initialize (app) {

  const authenticationSpec = path.join(__dirname,'api/authentication.yaml');
  const authenticationMiddleware = await useSwaggerMiddlewares(authenticationSpec, {
    router: routerOptions,
    validator: validatorOptions,
  });
  // NOTE the metadata must be mounted at root level!
  app.use(authenticationMiddleware.metadata);
  app.use('/v2/authentication', authenticationMiddleware.validator);
  app.use('/v2/authentication', authenticationMiddleware.router);
  app.use('/v2/authentication', authenticationMiddleware.ui);

  const mainSpec = path.join(__dirname,'api/swagger.yaml');
  const mainMiddleware = await useSwaggerMiddlewares(mainSpec, {
    router: routerOptions,
    validator: validatorOptions,
  });
  app.use(mainMiddleware.metadata);
  app.use(mainMiddleware.validator);
  app.use(mainMiddleware.router);
  app.use(mainMiddleware.ui);

  // Start the server
  http.createServer(app).listen(serverPort, () => console.log(`server lintening on port ${serverPort}`);
}

initialize(app);

With useSwaggerMiddlewares defined here

module.exports = function useSwaggerMiddlewares (swaggerSpec, {
  router: routerOptions, validator: validatorOptions,
}) {
  return new Promise((resolve, reject) => {
    try {
      // The Swagger document (require it, build it programmatically, fetch it from a URL, ...)
      const spec = fs.readFileSync(swaggerSpec, 'utf8');
      const swaggerDoc = jsyaml.safeLoad(spec);

      // Initialize the Swagger middleware
      swaggerTools.initializeMiddleware(swaggerDoc, (middleware) => {
        try {
          return resolve({
            // Interpret Swagger resources and attach metadata to request - must be first in swagger-tools middleware chain
            metadata: middleware.swaggerMetadata(),
            // Validate Swagger requests
            validator: middleware.swaggerValidator(validatorOptions),
            // Route validated requests to appropriate controller
            router: middleware.swaggerRouter(routerOptions),
            // Serve the Swagger documents and Swagger UI
            ui: middleware.swaggerUi()
          });
        } catch (error) {
          console.error(error);
          return reject(error);
        }
      });
    } catch (error) {
      console.error(error);
      return reject(error);
    }
  });
};